Lease credit and residual value variants
========================================

Run ``lease_variants.py`` or installed ``run_lease_variants()`` in R. Inputs
explicitly separate collectible customer claims, cancelled future rents and
retained residual carrying value. Net disposal cash is allocated once in the
same waterfall as the loss bridge. Supplied priorities and asset rights are
illustrative legal conventions, not inferred lease accounting or national law.

The operating lease has paid all 1,000 due and returns the vehicle as agreed.
There is no outstanding customer credit claim and no declared UTP or material
arrears. Sale proceeds 8,000 less costs 500 leave 7,500 against residual carrying
value 12,000: residual loss 4,500, credit loss zero, no credit default. Market loss
is evaluated separately and never promoted into a borrower default on its own.

The finance-lease default has an enforceable 12,000 credit claim, no separately
retained residual carrying value, and allocated sale cash 7,500: credit loss 4,500.
It is an explicitly different claim contract from the operating-lease case.

Early termination extinguishes three future 1,000 payments and substitutes an
1,800 termination claim plus a 200 condition charge only when the customer bears
that charge. The old rents are disclosed but are not added to the replacement
claim. Sale cash 1,500 less costs 500 recovers 1,000 of the 2,000 claim, leaving
credit loss 1,000 and residual loss 10,000. Combined loss 11,000 reconciles exactly
to the two disjoint carrying components minus total net cash. The control case
without customer responsibility has claim 1,800 and credit loss 800.

Cashflow default tests apply the supplied same-date economic test independently
of explicit UTP/material-arrears triggers. These are deterministic contract
scenarios, not estimated default frequencies or universal regulatory rules.
